Alternately, here’s the text from this video, so you may read the information if you like.

Aloha Everyone,
This is Elizabeth with Aloha Farms food forest in sunny Southern California, where we enjoy growing citrus fruit year-round. The 5 decades-old trees that were here when we moved in hadn’t been cared for in a while, but we found that with a little TLC, we were able to bring them back to outstanding health and they now produce some of the juiciest, most delicious fruit I’ve ever had.
Healthy trees are less likely to attract harmful pests. Our beautiful citrus trees were recently tested by the County of San Diego Department of Agriculture, when they placed traps in the trees for 6 weeks during January and February 2016 to see if they could trap exotic fruit flies, asian citrus psyllids, and other unwanted pests. They found that our trees had no pests – which is really great news.
Here are 4 things we did to improve the health of the dear old citrus trees:
1. Pruning – cut off dead or dying branches and stems, remove leaves or stems that are infested with bugs like scale or white fly, remove new growth from the interior of the tree to improve air circulation. These “Water Sprouts” grow vertically from lateral branches and can be removed entirely or pruned above a node to re-direct their growth.
2. Cover the soil under the tree in organic material, which feeds and protects the life-forms that grow in the soil allowing them to proliferate safely under the covering. This also moderates the soil temperature so that it doesn’t get too hot or too cold, and finally, helps retain the soil moisture by preventing it from evaporating.
3. Sprinkle the soil with epsom salt (magnesium sulfate) before a rain so that the rain will wash it into the soil. This really invigorates the trees.
4. Insert into the ground under the tree a 2′ – 3′ piece of ABS pipe or other pipe that’s 2″-3″ in diameter, leaving 2″ or so above the soil level. This will be your watering pipe, so you can water directly into the pipe with a hose, and the water will go right down to the roots. Before we installed our watering pipes, we could water for an hour on top of the soil, and it wouldn’t penetrate deeply into the root zone, so we definitely found this to be a tremendous improvement. We can fill the pipe a few times, and we have deep water penetration of the root zone.
5. This last tip I discovered, and it works well against flying insects that love to feed on new leaf growth. During periods of rapid new leaf growth, if the weather is dry, come out in the late afternoon/early evening and shower off the trees’ foliage with water from a hose. Whatever flying insects are on the tree will instantly fly away to go find drier places. I do this in the early evening so that the water won’t quickly evaporate from the leaves and the insects will stay away while the leaves are wet – and hopefully decide not to come back! This also washes off dust and the trees seem to enjoy a good shower – just like we do 

That’s it for now – I hope this information helps any of you who are growing fruit! Thank you for watching, and Aloha!!!